"If we increase the amplitude of transverse waves on a string, what happens to the speed of a wave along the string?"

It is increased

Explanation:

If the amplitude of a transverse wave in a string is increased, then also, the speed of that wave along the string also increases.

In transverse waves, the particles of the medium does move vertically, m either up or down and also moves at right angles to the direction of the wave. It should be noted also, that the wave amplitude of a transverse wave is defined as the difference in height between the crest(high) and the resting position(low).

The highest point particles of the medium reach is often tagged as the crest, while the lowest point is tagged as the resting position. The higher the height of the crests are, the greater the amplitude of the wave will be.

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